There is a multitude of products which are designed to conform to individual body parts. Examples of these products include chair seats, shoes and pillows, sporting equipment such as helmets, boots, and protective gear, and products for medical uses such as casts, braces and orthotics.
The purpose of these products is generally to provide the benefits of comfort, support, protection and shock absorption to the user. These products can be generic or, more preferably, can be customized to fit a particular individual's body part. With respect to customizable products, most can be fitted once, are not remoldable, and are usually very expensive.
In an effort to provide a low cost custom fitting athletic shoe, Reebok has introduced the Pump™. The Pump™ offers a customized fit by utilizing air bladders in conjunction with an air pump. The air bladders are deposed at selected locations on the interior of the shoe. The wearer can then activate the pump, thereby filling the bladders with pressurized air. This inflation allows the shoe to better conform to the shape of the wearer's foot. However, the drawback of this design is that the air bladders need to be inflated before and/or during each use. Further, this design does not offer significant shock absorption or protection.
Other athletic shoes on the market contain inserts of air or gel at various selected locations on the interior of the shoe so as to provide support and/or shock absorption. However, these inserts do not provide a customized fit. Additionally, in the case of the air inserts, the air tends to move from side to side during use, thereby reducing its motion control and effectiveness. Also, all of these products tend to wear out over time and become less effective.
Salomon of France has introduced a heat moldable removable inner boot with ethyl vinyl acetate (EVA) padding. The inner boot is placed over forced hat air blowers known as heat stacks that force hot air up into the liner, much like a heat gun. After the boot is warmed, the skier puts the boots on for a custom fit. While Salomon inner boot is an improvement from the products of the past, its possesses a number of draw backs. EVA offers limited shock offers limited shock absorption; it is too soft for heavier or advanced skiers; the temperature at which it must be molded, 120.degree. C., is too hot to be allowed to come into direct contact with the individuals skin whose body temperature is 37.degree. C.; it is not reusable more than five times; it is difficult to fit and therefore must be applied by a professional.
In an effort to achieve a custom fit, foams, silicone foams and silicones have been used for more than twenty years with mixed success. They are generally expensive, difficult to use and may generate hazardous fumes. These products must be fitted by a professional sales person and can only be fitted once. Additionally, since these products are not remoldable and can not be reused, if an error is made in the fitting process, the product must be discarded and the process restarted. Also, most of these products eventually break down and soften after a few months of use.
Applicant's U.S. Pat. No. 6,025,414 describes a composite which can be used to provide custom padding, cushioning and/or even constant support to a unique shaped part, and is heat moldable. This composite can be relatively heavy in some applications, and the composite has a tendency to slowly flow at the temperatures at which the composite is to provide the cushioning and support. The composite also can have relatively very high adhesion or be very sticky. This tendency to flow and the stickiness, often requires that the composite be contained in an enclosure such as a pouch or envelope. U.S. Pat. No. 6,025,414 is incorporated by reference.
Applicant's U.S. Pat. No. 7,900,380 discloses a user moldable and adjustable insert where the amount of gel in a chamber is selectively variable depending on the needs of a user. U.S. Pat. No. 7,900,380 is incorporated by reference.